1. Field of the Invention
The present invention relates to initiating, routing and scheduling conferences.
2. Background of the Invention
Conventional conferencing systems comprise a number of end-points communicating real-time video, audio and/or data streams over and between various networks such as WAN, LAN and circuit switched networks.
A number of conference systems residing at different sites may participate in the same conference, most often, through one or more MCU's (Multipoint Control Unit) performing switching functions to allow the audiovisual terminals to intercommunicate properly.
Video conferencing has been utilized for many years mostly on separated terminals with hardware and software tailored for videoconferencing. However, in recent years, video conferencing from a computer terminal or through a computer network has become feasible. The computer terminal is, for example, a personal computer having a camera and a microphone. The computer network can among others be a Local Area Network (LAN), a Public Switched Telephone Network (PSTN), or the Internet. Video conferencing requires a large amount of bandwidth and processing power and often quality levels of audio, video and data are not able to be maintained at high levels due to limitations on bandwidth and processing power. These limitations may originate from the computer network or the computer terminals.
Current video conferencing standards, usually separate a conference into streams for audio, video and data. The two standards that traditionally has been employed in video conferencing are: (1) ITU-T Recommendation H.320 (1996) Narrow-band visual telephone systems and terminal equipment and (2) ITU-T Recommendation H.323 (1997) Packet-based multimedia communications systems, both of which are hereby incorporated by reference.
A third standard, the Session Initiation Protocol (SIP) has traditionally had a profound impact on the voice world, and it is beginning to influence the video world as well. SIP provides signaling and call control means that are especially designed for the delivery of ‘advanced’ features such as IM, multimedia sessions (voice, video, IM, web conference . . . ), and presence. SIP interoperability promises to reduce the cost of telecommunication products and services as these devices and services promulgate from the realm of the vendors into products and services used by enterprises and consumers.
Desktop video has traditionally been run on a PC by launching a separate application designed for video only. In a video telephony environment, video is one of several communication medias users can take advantage of from a common, well-designed user interface. Furthermore, many soft client manufacturers are providing APIs that will allow video, voice, and the other communications mechanisms to be integrated into everyday workflow applications like Outlook, Microsoft Office Suite, CRM applications, ERP applications, etc. Video telephony is really less about making a video call and more about improving the ability to communicate at a distance in whatever workflow environment a user may be in.
Video-enabled soft clients running on a PC are required to perform significant processing in order to compress video images into data streams that can be effectively transmitted over the network. New, powerful PCs are available at a reasonable price that can take advantage of the latest video compression algorithms. The most common standards for video compression are H.263 and H.264. While both require significant processing power, H.264 is able to provide an image equivalent to H.263 but at roughly half the bandwidth. To achieve this level of compression, H.264 requires more processing power than does H.263. PCs are now available that can perform the processing needed to compress H.264 video streams.
In addition to more powerful computers and more effective compression techniques, another trend that has boosted deployment of desktop video is the development of low-priced web-cams of a relatively high quality. Also, it has become more common for computers to have integrated web-cams as well as microphones.